- 2022 Factory-verified
only in: Essence, with the Sport Touring Edition (HCR); 2022: Essence: O; not in the 2023 guide, where QH5 takes its place
Q78 Factory-verified
Documented applications
This page aggregates every documented appearance of Q78 in the Buick reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.